[Redirected to zope-dev] On 13 Dec 1999, Guido A.J. Stevens wrote:
In short, we crave for a way to use cvs on Zope object stores.
I've thought of two ways of doing this 'seemlessly', both involving writing a new Storage module for Zope. FSStorage - Store each non folderish object in an individual file in ascii pickle format For each folderish object, a directory is created and the actual ascii pickle data is stored in a 'magic' file in this directory. Caveats: If you use 'id' as the filename, ids will be restricted to those available on the underlying OS (including case issues), and there would need to be reserved id's (eg CVS, RCS, '__magic__'). Alternatives will give meaningless names (eg using a ascii representation of _p_oi). Undo would probably not be available Bonuses: May outperform existing FileStorage on certain hardware (eg. my NetApp 740) Allows integration with tools like CVS or RCS, although I have no idea if rollback could be done on individual objects. CVSStorage - As FSStorage, but store objects directly in a CVS repositary. Caveats: Speed. A fork tax would be required each time an object is read (to call the OS's cvs executable), unless someone wraps the CVS source into cvs.py (Might be easy with SWIG - I have no idea). Even without the fork tax, it will be slower accessing the object through CVS. And large memory caches don't help for writing objects... Bonuses: Point in time rollback Possible to add hooks to allow viewing of previous revisions of documents into Zope, perfect for Document Management products. Not only undo, but in theory it would be possible to support branching and merging if Zope became intelligent enough (loosly distributed databases anyone?) It might be worth using some variant of pickle that is more CVS friendly (ie. more linefeeds).
Has anybody been working on this? Has anybody come up with a more intelligent approach than diffing and patching wholesale xml exports? Do we need to wait for a different (non-monolithic) filestorage backend - is anybody working on /that/?
It doesn't exist yet, and I have plenty of other stuff to keep me busy at the moment.... -- ___ // Zen (alias Stuart Bishop) Work: zen@cs.rmit.edu.au // E N Senior Systems Alchemist Play: zen@shangri-la.dropbear.id.au //__ Computer Science, RMIT WWW: http://www.cs.rmit.edu.au/~zen